The present invention relates to a method and device for introducing a carburetted mixture under pressure in a chamber of a cylinder of a two stroke-internal combustion engine.
More particularly, the present invention provides an assistance device for controlling an automatic valve disposed between the end of a mixture feed duct and the chamber of the cylinder.
The use of valves is known, such as flaps or shutters, which cooperate with return means actuated under the effect of the pressure differences between each of the faces, for introducing a carburetted mixture in the chamber of a cylinder. However, because in particular of the inertial forces compared with the forces due to the pressure differences and possible unsteadiness of the return means when their operating frequency is close to their resonance frequency, these valves cannot be used when the pressure differences are too low and when the operating speed is too high.
The present invention provides a device having more particularly the advantages of prior automatic valve devices, such as thermal resistance, rapid opening and wide passage and which can be used in particular when the pressure difference between the chamber and the cylinder and the carburetted mixture feed duct is small.